The present invention relates to a headlamp system for a vehicle which is constituted to carry out beam control for a headlamp.
In an ordinary headlamp for a vehicle, a beam irradiation direction thereof is fixed. Therefore, a road provided ahead of the vehicle cannot be sufficiently irradiated during running on a curved road such as a mountain road or an intersection.
On the other hand, JP-A-8-192674 has disclosed a headlamp system for a vehicle in which beam irradiation is carried out toward a road provided ahead of a vehicle in a curving advance direction when a turn signal lamp is operated or a steering operation is performed, thereby enhancing a visibility during the running on the curved road.
Moreover, the shape of the road provided ahead of the vehicle is detected by means of a CCD camera. If beam control is carried out corresponding to the result of the detection, it is possible to more properly carry out the beam irradiation on the road provided ahead of the vehicle.
In a vehicle comprising a navigation device, furthermore, it is also possible to carry out the beam control for a headlamp by utilizing a route guidance function. The route guidance function is a function of setting a guide route from a current self-vehicle position to a running destination and providing information required for a driver in an image or a voice according to the guide route. If the beam control corresponding to the guide route is thus carried out, it is possible to properly perform the beam irradiation over the road provided ahead of the vehicle without requiring a complicated calculation as compared with the case in which the beam control corresponding to the result of detection of the shape of the road provided ahead of the vehicle is to be executed.
In the case in which the beam control for the headlamp is to be thus carried out by utilizing the route guidance function, however, the following problem arises.
More specifically, even if the self-vehicle runs along the guide route at the present time, it does not always run continuously along the guide route but gets out of the guide route in some cases. In those cases, usually, the guide route is re-searched by a navigation device. However, there is a problem in that proper beam control cannot be carried out until the re-search is completed and a new guide route is set.
The invention has been made in consideration of such circumstances and has an object to provide a headlamp system for a vehicle constituted to carry out the beam control for a headlamp in which beam control utilizing the route guidance function of a navigation device can be performed, and furthermore, predetermined beam control can be executed also in the case in which a self-vehicle gets out of a guide route.
The invention attains the object by devising the beam control when a self-vehicle comes to an intersection in consideration of the fact that the self-vehicle generally gets out of a guide route when passing through the intersection.
More specifically, the invention provides a headlamp system for a vehicle comprising a headlamp for irradiating a forward part of the vehicle, beam control means for controlling a beam irradiated by the headlamp, and a navigation device constituted to set a guide route from a current self-vehicle position to a running destination,
wherein, in such a state that a self-vehicle runs along the guide route,
the beam control means carries out the beam control in a navigation associating mode corresponding to the guide route if an intersection is not present between the current self-vehicle position and a position that the self-vehicle is to reach after a predetermined time in the guide route, and
carries out the beam control in a control mode other than the navigation associating mode until the self-vehicle passes through at least an intersection present before the position that the self-vehicle is to reach if any.
The specific contents of the beam control to be carried out by the xe2x80x9cbeam control meansxe2x80x9d are not particularly restricted but it is possible to employ control in which the irradiation direction, range or amount of a beam to be irradiated from the headlamp or their proper combination is variable, for example.
If the xe2x80x9cintersectionxe2x80x9d is a point in which three or more roads merge, a configuration thereof is not particularly restricted but may be an intersection of a crossroad, a T-shaped road or a five-forked road or may be a Y-shaped diverging point or merging point.
The specific contents of the xe2x80x9ccontrol mode other than the navigation associating modexe2x80x9d are not particularly restricted but it is possible to employ a road shape corresponding mode for carrying out beam control corresponding to the shape of the road provided ahead of the vehicle or a turning angle corresponding mode for carrying out beam control corresponding to a vehicle turning angle, for example.
As shown in the structure, the headlamp system for a vehicle according to the invention comprises the beam control means for controlling a beam irradiated by the headlamp and the navigation device having a route guidance function. In such a state that the self-vehicle runs along the guide route, the beam control means carries out the beam control in the navigation associating mode corresponding to the guide route in the case in which an intersection is not present between the current self-vehicle position and the position that the self-vehicle is to reach after a predetermined time in the guide route, while it carries out the beam control in the control mode other than the navigation associating mode until the self-vehicle passes through at least the intersection in the case in which the intersection is present before the position that the self-vehicle is to reach. Therefore, the following functions and effects can be obtained.
More specifically, when the self-vehicle runs along the guide route, the beam control is carried out in the navigation associating mode if the intersection is not present in a forward part over the guide route for awhile. Therefore, it is possible to properly carry out beam irradiation over the road provided ahead of the vehicle without requiring a complicated calculation for the beam control (without applying a great burden to the beam control means). On the other hand, when the self-vehicle runs along the guide route, the beam control is carried out in the control mode other than the navigation associating mode if the intersection is present ahead of the vehicle. Therefore, even if the self-vehicle gets out of the guide route when passing through the intersection, the beam control itself is carried out continuously. Consequently, it is possible to properly carry out the beam irradiation over the road provided ahead of the vehicle.
According to the invention, thus, the beam control utilizing the route guidance function of the navigation device can be carried out, and furthermore, predetermined beam control can be performed also in the case in which the self-vehicle gets out of the guide route in the headlamp system for a vehicle which is constituted to execute the beam control for the headlamp.
With the structure described above, if the self-vehicle gets out of the guide route when passing through the intersection in such a state as to run along the guide route, the beam control is carried out in the control mode other than the navigation associating mode until the guide route is re-searched by the navigation device and a new guide route is set, and the beam control is carried out in the navigation associating mode after the new guide route is set. Thus, proper beam control can be carried out continuously, and furthermore, the beam control can be performed in the navigation associating mode as much as possible. Consequently, it is possible to relieve the burden of the beam control means.
The specific contents of the xe2x80x9ccontrol mode other than the navigation associating modexe2x80x9d are not particularly restricted as described above. With such a structure as to include the road shape corresponding mode for carrying out the beam control corresponding to the shape of the road provided ahead of the vehicle, also in the case in which the self-vehicle gets out of the guide route, it is possible to properly perform the beam irradiation over the road provided ahead of the vehicle in almost the same precision as the beam control in the navigation associating mode.
The specific contents of the xe2x80x9cbeam control in the navigation associating modexe2x80x9d are not particularly restricted. With such a structure that the position that the self-vehicle is to reach after a predetermined time in the guide route is set to be a target position, the road provided ahead of the vehicle can be irradiated sufficiently.